| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.phoenix.util; |
| |
| |
| /** |
| * Utilities for computing an object's size. All size measurements are in bytes. |
| * Note, all of the sizes here, but especially OBJECT_SIZE and ARRAY_SIZE are estimates and will |
| * depend on the JVM itself (and which JVM, 64bit vs. 32bit, etc). |
| * The current values are based on: |
| * Java HotSpot(TM) 64-Bit Server VM/14.2-b01 |
| * |
| * (Uncomment out and run the main w/ appropriate object to test) |
| * Also, see this link: |
| * https://sites.google.com/a/salesforce.com/development/Home/old-wiki-home-page/i-wish-i-knew#TOC-How-to-measure-the-size-of-a-Java-O |
| * For another way to measure. |
| */ |
| public class SizedUtil { |
| public static final int POINTER_SIZE = 8; // 64 bit jvm. |
| public static final int OBJECT_SIZE = 16; // measured, see class comment. |
| public static final int ARRAY_SIZE = 24; // measured, see class comment. |
| public static final int CHAR_SIZE = 2; |
| public static final int INT_SIZE = 4; |
| public static final int LONG_SIZE = 8; |
| |
| public static final int TREE_MAP_SIZE = OBJECT_SIZE + INT_SIZE * 2 + POINTER_SIZE * 2; |
| public static final int MAP_ENTRY_SIZE = OBJECT_SIZE + 3 * POINTER_SIZE + INT_SIZE; |
| public static final int IMMUTABLE_BYTES_WRITABLE_SIZE = OBJECT_SIZE + INT_SIZE * 2 + ARRAY_SIZE; |
| public static final int IMMUTABLE_BYTES_PTR_SIZE = IMMUTABLE_BYTES_WRITABLE_SIZE + INT_SIZE;// Extra is an int field which caches hashcode. |
| public static final int KEY_VALUE_SIZE = 2 * INT_SIZE + LONG_SIZE + 2 * ARRAY_SIZE; |
| public static final int RESULT_SIZE = OBJECT_SIZE + 3 * POINTER_SIZE + IMMUTABLE_BYTES_WRITABLE_SIZE; |
| public static final int INT_OBJECT_SIZE = INT_SIZE + OBJECT_SIZE; |
| public static final int LONG_OBJECT_SIZE = LONG_SIZE + OBJECT_SIZE; |
| public static final int BIG_DECIMAL_SIZE = |
| OBJECT_SIZE + 2 * INT_SIZE + LONG_SIZE + 2 * POINTER_SIZE + |
| OBJECT_SIZE /* BigInteger */ + 5 * INT_SIZE + ARRAY_SIZE /*mag[]*/ + 2 * INT_SIZE /* est mag[2] */; |
| |
| private SizedUtil() { |
| } |
| |
| public static int sizeOfTreeMap(int size) { |
| return TREE_MAP_SIZE + (OBJECT_SIZE + INT_SIZE + POINTER_SIZE * 5) * size; |
| } |
| |
| public static int sizeOfArrayList(int capacity) { |
| return SizedUtil.OBJECT_SIZE + SizedUtil.POINTER_SIZE + SizedUtil.INT_SIZE + SizedUtil.ARRAY_SIZE + SizedUtil.POINTER_SIZE * capacity; |
| } |
| |
| public static long sizeOfMap(int nRows) { |
| return sizeOfMap(nRows, SizedUtil.POINTER_SIZE, SizedUtil.POINTER_SIZE); |
| } |
| |
| public static long sizeOfMap(int nRows, int keySize, int valueSize) { |
| return SizedUtil.OBJECT_SIZE * 4 + sizeOfArrayList(nRows) /* key set */ + nRows * ( |
| SizedUtil.MAP_ENTRY_SIZE + /* entry set */ |
| keySize + // key size |
| valueSize); // value size |
| } |
| } |